This Jackson ANSI Grade 1 Extended Spindle
Overhead Concealed Closer features a longer spindle (approximately 7/8
in (22 millimeter)), the preferred length when used in conjunction with Patch
Hardware Fittings. The closer comes standard with an adjustable hydraulic
backcheck feature that provides the ultimate protection from wind or violent
door swings to prevent damage to the closer and opening without impeding normal
traffic flow. Also standard are dual action valves for closing operation (one
valve for closing, one valve for latching). 90º and 105º Hold Open and Non
Hold-Open models are available. Interchangeable with standard Jackson and
similar brands of Overhead Concealed Closers.